int pthread_rwlock_timedwrlock(pthread_rwlock_t *rwlock, const struct timespec *abs_timeout)
{
int thread_id, ret = 0;
if (rwlock == NULL)
return EINVAL;
pthread_mutex_lock(&rwlock->lock);
thread_id = __get_thread_id();
if (__unlikely(!write_precondition(rwlock, thread_id))) {
/* If we can't read yet, wait until the rwlock is unlocked
* and try again. Increment pendingReaders to get the
* cond broadcast when that happens.
*/
rwlock->pendingWriters += 1;
do {
ret = pthread_cond_timedwait(&rwlock->cond, &rwlock->lock, abs_timeout);
} while (ret == 0 && !write_precondition(rwlock, thread_id));
rwlock->pendingWriters -= 1;
if (ret != 0)
goto EXIT;
}
rwlock->numLocks ++;
rwlock->writerThreadId = thread_id;
EXIT:
pthread_mutex_unlock(&rwlock->lock);
return ret;
}
_WCRTLINK int pthread_setschedparam(pthread_t __thr, int __policy, const struct sched_param *__param)
{
pid_t tid;
tid = __get_thread_id(__thr);
return( sched_setscheduler(tid, __policy, __param) );
}
int pthread_rwlock_tryrdlock(pthread_rwlock_t *rwlock)
{
int ret = 0;
if (rwlock == NULL)
return EINVAL;
pthread_mutex_lock(&rwlock->lock);
if (__unlikely(!read_precondition(rwlock, __get_thread_id())))
ret = EBUSY;
else
rwlock->numLocks ++;
pthread_mutex_unlock(&rwlock->lock);
return ret;
}
_WCRTLINK int pthread_getschedparam(pthread_t __thr, int *__policy, struct sched_param *__param)
{
int ret;
pid_t tid;
ret = 0;
tid = __get_thread_id(__thr);
if(__policy != NULL)
*__policy = sched_getscheduler(tid);
if(__param != NULL)
ret = sched_getparam(tid, __param);
return( ret );
}
int pthread_rwlock_trywrlock(pthread_rwlock_t *rwlock)
{
int thread_id, ret = 0;
if (rwlock == NULL)
return EINVAL;
pthread_mutex_lock(&rwlock->lock);
thread_id = __get_thread_id();
if (__unlikely(!write_precondition(rwlock, thread_id))) {
ret = EBUSY;
} else {
rwlock->numLocks ++;
rwlock->writerThreadId = thread_id;
}
pthread_mutex_unlock(&rwlock->lock);
return ret;
}
int pthread_rwlock_timedrdlock(pthread_rwlock_t *rwlock, const struct timespec *abs_timeout)
{
int thread_id, ret = 0;
if (rwlock == NULL)
return EINVAL;
pthread_mutex_lock(&rwlock->lock);
thread_id = __get_thread_id();
if (__unlikely(!read_precondition(rwlock, thread_id))) {
rwlock->pendingReaders += 1;
do {
ret = pthread_cond_timedwait(&rwlock->cond, &rwlock->lock, abs_timeout);
} while (ret == 0 && !read_precondition(rwlock, thread_id));
rwlock->pendingReaders -= 1;
if (ret != 0)
goto EXIT;
}
rwlock->numLocks ++;
EXIT:
pthread_mutex_unlock(&rwlock->lock);
return ret;
}
int pthread_rwlock_unlock(pthread_rwlock_t *rwlock)
{
int ret = 0;
if (rwlock == NULL)
return EINVAL;
pthread_mutex_lock(&rwlock->lock);
/* The lock must be held */
if (rwlock->numLocks == 0) {
ret = EPERM;
goto EXIT;
}
/* If it has only readers, writerThreadId is 0 */
if (rwlock->writerThreadId == 0) {
if (--rwlock->numLocks == 0)
_pthread_rwlock_pulse(rwlock);
}
/* Otherwise, it has only a single writer, which
* must be ourselves.
*/
else {
if (rwlock->writerThreadId != __get_thread_id()) {
ret = EPERM;
goto EXIT;
}
if (--rwlock->numLocks == 0) {
rwlock->writerThreadId = 0;
_pthread_rwlock_pulse(rwlock);
}
}
EXIT:
pthread_mutex_unlock(&rwlock->lock);
return ret;
}
